Die for use with a punch



Sept. 18, 1951 N. T. HERMANN DIE FOR USE WITH A PUNCH Filed March 18, 1949 HHHI II I l "H I INVENTOR -N. THERMA NA! 8) Q P ATTORNEY Patented Sept. 18, 1951 DIE FOR USE WITH A PUNCH Norman T. Hermann, Eatontown, N. J., assignor to Western Electric Company, Incorporated, New York, -N. Y., a corporation of New York Application March 18, 1949, Serial No. 82,116

' of steel and requiring considerable expense, time and skilled labor for their initial manufacture, may be-ground a limited number of times to recondition them for further use, after which the die is destroyed and a completely new die must be provided.

An object of the invention is to provide a die. which is simple in structure, inexpensive to manufacture and the major portion of which may be utilized indefinitely.

With this and other objects in view, the invention comprises a die having a permanent member with an aperture positioned in alignment with a punch, and a metal strip having an aperture therein conforming to the contour of the punch. The metal strip is positioned on the permanent member with its aperture in alignment with the punch. The aperture in the member is filled with a metal which has a lower melting point than the metals of the other members of the die and is therefore softer than these members. In the metal is an aperture cooperating with the aperture in the strip to form a die cavity in the member. The die is initially formed by pouring the soft metal in a molten state in the aperture of the member around the punch which forms the cavity therein. After the die is formed, the punch is removed therefrom.

Other objects and advantages will be apparent from the following detailed description, when considered in conjunction with the accompanying drawings, wherein Fig. 1 is a front elevational view of the die shown in cooperation with a punch; and

Fig. 2 is a top plan view of the die.

Referring now to the drawing, numeral designates a mounting plate which may be secured to the bed of a punch press, the mounting plate having an aperture ll therethrough which may also be aligned with the conventional aperture in the bed of the press. The press includes the conventional ram l2 which is reciprocated in a given path during the operating cycles of the press. The ram carries a tool holder l4 mounted for vertical movement with the ram and the conventional guide sleeves l5 associated with guide pins l6 extending vertically from the mounting plate I 0. A punch I8 is carried by the tool holder l4 and is of a given cross-sectional ill 2 contour depending upon the contour of the part to be blanked.

The die includes a permanent member 20 mounted by the aid of screws 2| on the mounting plate I0 and provided with a central aperture 22 extending to a position short of the bottom of the main member where it opens into an aperture 23 registering with the aperture ll of the mounting plate. Aligned grooves 25 are formed in the upper surface of the member 20 to receive an apertured strip 26. The strip 26 is formed of spring steel and has an aperture 21 therein conforming to the contour of the punch 98, the aperture having been previously formed therein by the punch IS. The strip26, placed centrally in the member 29, extending over the aperture 22 and having its ends resting in the grooves 25, constitutes the upper portion of the die and provides the main or cutting portion of the die cavity. The remaining portion 28 of the die is formed of a softer material, that is, a material having a lower melting point than any of the other portions of the die. This material is commercially known and is similar to lead.

In actual structure, the softer material or metal disposed in the aperture 22 in a molten state at which time the lower end of the aperture 22 is closed by filling the aperture I I with a suitable material, such as a sealing compound 30. The strip 26 is disposed in place with its ends nested in the grooves 25 and its aperture 21 in alignment with the punch I8 and the punch is lowered until its leading end rests upon or is embedded in th sealing compound 36 at t e time the material 28 is poured. The material or metal 28 therefore has a die cavity which is accurate in conforming to the punch and which will require no machining. The metal 28 will also extend upwardly along the side edges of the strip 26 and in this manner firmly secure the strip as a solid unit with the other members of the die.

After the die has been formed, the punch !8 may be removed, after which the sealing compound 38 may be,- removed from the aperture H rendering the die ready for use. If desired, the die may be machined in the conventional manner by grinding the strip 25. However, the cost of reconditioning the die would be less expensive than grinding the die or strip. The die may be reconditioned by melting the material 28, removin the worn strip -Z6 and substituting therefor a new strip 25. Reconditioning of the die re- .quires only a supply of the strips 26 which may be produced at any tim by the punch and die itself.

It is to be understood that the abov described arrangements are simply illustrative of the application of the principles of the invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

1. A die for use with a reciprocable punch having a given cross-sectional contour, the die comprising a main member having an aperture therein larger than the punch and disposed in general alignment therewith, a metal strip disposed on the main member and having an aperture therein conforming to the punch, and a metal member substantially filling the aperture of the member excepting an aperture conforming to the punch and in alignment with the aperture of the strip to cooperate therewith in forming a die cavity.

2. A die for use with a reciprocable punch having a given cross sectional contour, the die comprising a main metal member having an aperture therein larger than th punch and disposed in general alignment therewith, a metal strip disposed on the main member and having an aperture therein formed by the punch, and a metal having a lower melting point than the metals of the strip and main member filling the aperture in the main member to support the adjacent portion of the strip and having an aperture therein conforming to the punch and cooperating with the aperture in the strip to form a die cavity.

main member filling the aperture in the main member to support the adjacent portion of the strip and hold the strip against displacement, the metal also having an aperture therein conforming to the punch and cooperating with the aperture in the strip to form a die cavity.

NORMAN T. HERMANN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Sedgwick et al. Nov. 26,1940 

